Spark plug



June 16, 1925 1,542,504

w. A. HEIDE SPARK PLUG Filed Jan. 29, 1925 if I v ,6 g W lfee'de,

Patented June 16 1925.

WILLIAM A. HEIDE, F DETROIT, MICHIGAN.

SPARK PLUG.

Application filed January 29, 1923. Serial No. 615,727.

To all 1071 am it may concern:

Be it known that 1, WILLIAM A. Huron, a citizen of the United States, residing at Detroit, in the county of lVayne and State of Michigan, have invented a new and useful Spark Plug, of which the following is a specification..

This invention relates to spark plugs, one of its objects being to provide a device of this character the parts of which can be assembled and taken apart readily, said spark plug including a central electrode the terminal of which can be adjusted angularly relative to a tixedelectrode, thus to vary the size of the spark gap.

Another object is to provide a novel arrangement of insulating means.

A stillfurther object is to provide a central electrode which can be adjusted longitudinally relative to the casing or shell of the spark plug.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts which will be hereinafter more full described and pointed out in the claims.

In the accompanying drawing, which is a central longitudinal section through a spark plug, the preferred form of the in- \ention has been shown.

Referring to the drawing by characters of reference 1 designates the shell of the spark plug having the usual tapered threaded end portion 2 and the opening extending longitudinally through this shell is slightly tapered inwardly from both ends toward the center of the shell as shown at 3.

Fxtending into the shell from opposite ends thereof are oppositely arranged tapered plugs 4 and 5 preferably though not necessarily formed of insulating'material. The inner or small ends of these plugs can, if desired, be spaced apart as shown at 6 so as to receive a gasket 6' of compressible material between them. A sheet or sheets 7 of mica or the like can be extended around the plugs so that when the plugs are forced toward each other they will bind the mica against the wall of the opening in the shell 1 and thus hold it in place securely.

A tubular tie bolt 8 is extended longitudinally through the plugs and is provided at one end with a head 9 while its other end is screw threaded as at 10. Head 9 is adapted to engage the large end of plug 5 while the threaded end 10 is adapted to be engaged by a nut 11 bearing against the largeend of the plug 4. By tightening the nut the plugs will be forced toward each other and will become properly centered in the shell 1 so as to clamp the layer of insulating material against the wall of the opening 3.

Extending longitudinally through the tie bolt 8 is a tubular core 12 having its end portions screw threaded as shown at 13 and 14, and provided with a head 12, by which the tubular core 12 can be rotated readily.-

The threads 13 engage one end of the tie bolt 8 while the threads 14 extend beyond the other end of the tie bolt and do not engage it. One or-more longitudinal grooves 15 can be provided in the outer surface of the core 12 and extend from the threads 13 toward the other end of the core, intersecting the threads 14. The outer end of the core is adapted to support an adjusting nut 16 engaging the threaded end portions 17 0 an electrode 18. This electrode extends through and is adapted to be rotated within the core 12 and has a collar 19 adapted to be drawn against one end of the core 13. A terminal 20 extends from the collar 19 and is offset laterally and adapted to cooperate with a fixed terminal 21 preferably located between the cylinder bore B and the intake port P of the engine to which the spark is attached. A look nut 22 also engages a threaded end 17 of the electrode and a binding nut 23 is adapted to engage said end 17 and cooperate with the nut 22 to secure the terminal of a wire to the electrode as shown at 24.

It will be understood that by loosening the nuts 16, 22 and 23 the electrode 18 can be rotated so as to bring itsterminal 20to any desired position relative to the electrode 21, thus to vary the size of the spark gap. By then tightening nut 16 the collar 19 will be drawn tightly against core 12 so as to hold the electrode against accidental rotation. Obviously by rotating the core 12 within the tie bolt 8 the electrode 18 can be shifted longitudinally toward or from the electrode 21, there being a nut engaging the threaded portion 14 of the core and bearing on the end of the tie bolt 8 so as to act as a lock nut to hold the core against accidental rotation.

As before pointed out the nut 11 constitutes a means for adjusting the plugs 4 and 5 toward each other, thereby to clamp the insulating sheet 7 against the shell 1 and hold the parts properly assembled.

It will be noted that this spark plug constitutes an etficient seal to prevent leakage of gas. Furthermore by having the groove or grooves 15 any heated air or moisture is free to escape readily from the center of the plug. The outer end of electrode 18 is flattened at 26 so that the electrode can be 1'0- tated readily to shift the terminal 20 relative to the electrode 21.

Vhat is claimed is:

1. A spark plug including a shell, opposed tapered plugs the-rein, a tubular tie bolt extending through the plugs and constituting means for adjusting the plugs to- Ward each other, a tubular core adjustable longitudinally within the tie bolt and having a longitudinal "groove extending to one end thereof, an electrode mounted for rotation within the core, a collar on the electrode bearing against the core, an offset terminal on the electrode, and means engaging the electrode and core for holding the electrode against movement relative to the core.

2. A spark plug including a shell, opposed tapered plugs within and insulated from the shell, a tubular tie bolt extending through the plugs for holding them wedged within the shell, a tubular core extending longitudinally through the bolts, an electrode extending through and rotatable within the including a shell, opposed tapered plugs therein and insulated therefrom, a tubular tie bolt extending through the plug for holding them wedged within the shell, a tubular (ore extending longitudinally through the tie bolt, an electrode extending longitudinal- L ly through the core and having an otlset terminal, said electrode being rotatable within the core to swing the terminal rclative to the fixed terminal, means upon the electrode and cooperating with the core for holding said electrode against rotation, said core being adjustable longitudinally within the tie bolt to shift the electrode bodily toward or from the fixed terminal, and means for holding the tie bolt against adjustment. In testimony that I claim the foregoing as my own, I have hereto affixed my signa ure in the presence of two witnesses.

WILLIAM A. HEllJlC.

ll'itnesses M. G. CRONGEYER, F. A. GRONGEYER. 

